Acid indolephenylmethane dyestuffs



Patented Mar. 28, 1939 UNITED STATES PATENT OFFICE ACIDINDOLEPHENYLMETHANE DYESTUFFS tion of Delaware No Drawing.

Application November 26, 1935,

Serial No. 51,679. In Germany November 27,

2 Claims. (01. zoo-4,19)

The present invention relates to acid indolephenylmethane dyestuffs.

We have found that acid triphenlymethane dyestuffs of very goodproperties of fastness and 5 clear tints maybe made by condensing anindole which contains in I-position an alkyl group, for instance, amethylor ethyl group and in 2-position an alkyl group, for instance,methyl or ethyl group, or a phenyl group and in 3-position apara-chloroor para-akloxy-benzoyl radical, with a secondary or tertiaryaromatic amine, including those of the heterocyclic series, then causingthe para-chlorine atom or the para-alkoxy-group respectively of thecondensation product to react with a primary aromatic amine whichcontains an alkoxy-group, for instance, the methoxy or ethoxy group, inpara-position to the aminogroup, by which operation hydrogen halide orthe corresponding alcohol is set free, and finally sulfonating theproduct obtained. It is also possible first to sulfonate the primarycondensation product and subsequently to cause it to react with theprimary aromatic amine which contains an alkoxy-group in para-position.

The indoles substituted in 1-, 2, and 3-positionused as parent materialsare easily obtainable by causing to react the reaction product from anarylide of a benzoic acid with phosphorus oxy-V chloride, with an indolesubstituted in 1- and 2-position and treating the condensation productwith a dilute acid. Thereby the arylide radical is split off withformation of, for instance, an indolylphenylketone.

The products obtainable according to the present process are newdyestuffs of the triphenylmethane series, for instance dyestuffs of thefollowing probable formula are obtained:

allkyl, N

wherein X means an alkyl or a phenyl group,

R means the radical, bound at a carbon atom,

of an aromatic compound containing a secondary or tertiary nitrogen atomand Y means that the compounds contain a further sulfonic acid group.

The following examples serve to illustrate the invention, but they arenot intended to limit it thereto, the parts being by weight:

1. 34.6 parts of l-methyl-Z-phenyl-3-parachlorobenzoyl-indole and 22.5parts of ethylbenzyl-meta-toluidine are condensed with each other in thepresence of 30.7 parts of phosphorus oxychloride as usually, forinstance, by melting at about C. to C. on the water-bath. The greendyestufi obtained, which is insoluble in water, is sulfonated and thenmelted with paraphenetidine at C. to C. There is obtained a dyestufi ofthe following probable formula:

which in the form of its sodium salt dyes wool and silk reddish bluetints of very good fastness to light, great clearness and good color inartificial light.

The l-methyl-2-phenyl-3-para-chlorobenzoylindole used as parent materialis obtainable, as already mentioned in the opening paragraph, asfollows:

92.4 parts of para-chlorobenzanilide, 82.8 parts of1-methyl-2-phenylindole and 184.5 parts of phosphorus oxylchloride areheated to 100 C. to 105 C., while stirring, and this temperature ismaintained for 5 hours. Thereupon, the mass is poured into hot dilutehydrochloric acid, while stirring, and the whole is maintained forseveral hours at water-bath temperature. After cooling, the Whole isfiltered and the solid matter is dried and recrystallized from alcoholand ligroin.

The 1-methyl-2-phenyl-3-para-chlorobenzoylindole thus obtained melts at158.5 C.

2. By using in Example 1 instead of the ethylbenzyl-meta-toluidine 21.1parts of ethylbenzylaniline and otherwise proceeding as indicated inthat example, a dyestuif is obtained which in the form of its sodiumsalt dyes woo-l and silk blue tints of a somewhat more reddish shadethan that of the tints obtainable according to Example 1 and of similargood properties.

3. The condensation of 34.6 parts of l-methyl-2-phenyl-3-para-methoxybenzoylindole with 20.0 parts ofbenzyl-ortho-toluidine in the presence of 30.7 parts of phosphorusoxychloride at about C. to about 0., yields a basic green dyestuff whichis insoluble in water. It is melted with para-phenetidine at C. to C.and then sulfonated. There is obtained a dyestuff of the followingprobable formula:

sulfonated yielding a product which in the form of its sodium salt dyeswool and silk clear very reddish blue tints of very good fastness tolight and good color in artificial light. The dyestufi has the followingprobable constitution:

soma

a I CH:

5. By substituting in Example 4 for the dimethylaniline therein used20.0 parts of benzylortho-toluidine and sulfonating the green dyestufithus formed, there is obtained, after melting with para-anisidine at 120C. to 125 C., a dyestufi which in the form of its sodium salt dyes wooland silk clear violet tints of very good fastness to light and very goodcolor in artificial light.

6. 34.6 parts of 1-methy1-2-pheny1-3-parachlorobenzoylindole arecondensed by boiling under refiux with 19.6 parts of N-ethylcarbazole in200 parts of benzene in the presence of 16 parts of phosphorousoxychloride. The green dyestufi obtained is melted with para-phenetidineas above described, and then sulfonated. There is thus obtained adyestuff of the following probable constitution:

CIHB

which in the form of its sodium salt dyes wool and silk reddish bluetints of very good fastness to light and of good color in artificiallight.

7. By substituting for the N-ethylcarbazole used in Example 6 20.8 partsof 1-methyl-2- phenylindole and proceeding otherwise as indicated inthat example a blue dyestufi of the following probable constitution isobtained:

OIHI

which in the form of its sodium salt dyes wool and silk tints of veryfood fastness to light and very good color in artificial light.

We claim: which in the form of its sodium salt dyes wool 1. The compoundf th f rm la; and silk tints of very good fastnessv to light and i verygood color in artificial light.

3 2. The process which comprises condensing an indole compound of theformula: 5 I Hols-more 5 CCoH -S0t E I] l ooQ-m c c I i l-05H! (I311;I'm 5 with l-methyl-2-phenylindole; melting the prod- 16 net obtainedwith para-phenetidin and sulfonating the reaction product.

PAUL WOLFF.

20 0 WIIHELM WERNER. 20

